This invention relates generally to turbine engines and, more particularly, to a gear driven booster for a turbine engine.
Turbine engines typically include a high pressure shaft and a low pressure shaft. The high pressure shaft connects a high pressure compressor to a high pressure turbine. The low pressure shaft connects a low pressure compressor, or booster, to a low pressure turbine. The booster is located upstream from the high pressure compressor which is located upstream from the high pressure turbine. The low pressure turbine is located downstream from the high pressure turbine. A combustor is between the high pressure compressor and the high pressure turbine. Further, a fan may be connected to the low pressure shaft upstream of the booster.
One way to generate additional thrust in a turbine engine is to increase the rotational speed of the low pressure shaft, thereby increasing the speed of the fan, booster, and low pressure turbine, which increases engine flow and pressure ratio. Another way to generate additional thrust is to either increase fan flow or increase fan pressure ratio, or both, at the same rotational speed of the low pressure shaft. Normally, increased thrust is obtained in conjunction with an increase in inlet temperature to the high pressure turbine and the low pressure turbine. The increased thrust, also normally results in additional horse power transmitted by the low pressure turbine to the booster and fan by the low pressure shaft.
Increased thrust therefore is normally obtained with additional complexities and costs associated with increased turbine temperatures such as more expensive materials, having to cool additional low pressure turbine stages, and increased power being transmitted by the low pressure turbine shaft.
Accordingly, it would be desirable to provide a turbine engine configuration that generates increased thrust, while utilizing existing low pressure shaft technology. In addition, it would be desirable for the engine to generate increased thrust without the need for cooling any of the low pressure turbine stages.